中國有色金屬學(xué)報(bào)(英文版)
Transactions of Nonferrous Metals Society of China
| Vol. 36 No. 1 January 2026 |
（a Key Laboratory of LCR Materials and Devices of Yunnan Province, School of Materials and Energy, Yunnan University, Kunming 650091, China;
b Division of Energy Science, Lule？ University of Technology, Lule？ 97187, Sweden;
c School of Materials Science and Engineering, Jiangsu University, Zhenjiang 212013, China;
d Electron Microscopy Center, Yunnan University, Kunming 650091, China）
Abstract:The age-hardening response, mechanical, and corrosion-resistant properties of AA7085 alloys with and without the addition of 0.3 wt.% scandium (Sc) were compared. Using advanced techniques such as aberration-corrected transmission electron microscopy and first-principles calculations, the underlying micromechanisms of Sc microalloying were revealed. Results show that the increase in strength of the AA7085-Sc alloy is mainly attributed to the decreased Al grain size and increased number density of both Al3Sc@Al3(Sc,Zr) core-shell nanoparticles and Sc-containing ηp and GP-ηp nanoprecipitates. Strong strain fields and evident electron transfer from Zr to the neighboring matrix Al atoms exist at the Al3Sc@Al3(Sc,Zr)/Al interface. The Sc doping in GP-ηp and ηp suppresses the GP-ηp → ηp transformation. Modified corrosion resistance of the AA7085-Sc alloy compared with AA7085 alloy is associated with the fine grain boundary precipitates of η phases and narrow precipitation free zone. The reasons of property changes of AA7085 alloy after Sc microalloying are explored based on the multiscale microstructural characterization.
Key words: 7085 aluminum alloy; Sc microalloying; microstructure; property; transmission electron microscopy
